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Limits on Dust in Rich Clusters of Galaxies from the Color of Background Quasars

Dan Maoz
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Abstract

I measure the V-I color distribution of two samples of radio-selected quasars. Quasars from one sample are projected on the sky within 1 degree of a rich foreground Abell cluster of galaxies, while quasars from the other sample are more than 3 degrees from any such cluster . There is no significant difference between the color distributions of the two samples. The 90\% upper limit on the relative reddening between the two samples is E(B-V)=0.05 mag. This result limits the allowed quantity of smoothly distributed dust in rich clusters, and contradicts previous indications for the existence of such a component.

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Dan Maoz. 1995-08-20. Limits on Dust in Rich Clusters of Galaxies from the Color of Background Quasars. https://doi.org/10.1086/309833

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